an value characterizing the low fertility group. As historical ests that such a reduction, if it occurs, may come about fairly s within 2 or 3 decades or an even shorter time—the potential age structure and on the rate of population growth may be ar. Accordingly and in sharp contrast to the traditional apis preoccupied with the relation of population size to "re-)re of the now prevailing theory on the economics of fertility primarily on the implications of these two demographic ransformation of the age structure and the change in the rate rowth. drops the young-age dependency falls. With the size of the force remaining unaffected in the short-run total, output will would be in the absence of a fertility decline. But as the given to be distributed among a smaller number of persons, income dative to what it would be had no fertility decline taken place. >r-all advantage implicit in the transformation of the age distri-ist when eventually a new equilibrium state is reached. This is IB comparison of the high- and low-fertility steady state age of fertility will result in a deceleration of population growth , in a lower rate of steady state growth than would be the case d high fertility. With a lower rate of growth the efforts re- 0 keep the capital stock per head constant will be smaller or, 1 a given level of effort the slower-growing population will be ; capital per head faster than with a high rate of growth. The "elt to some extent soon after fertility starts to decline but importance once the arrival of the cohorts affected by fertil-s to slow down the rate of growth in the labor-force ages. cor and against Lowered Fertility. Further advantages of fer-are discerned by various authors as working through the same 1 amplifying and reinforcing these two major effects. Q asserted that with higher income per capita not only savings e larger but also that a higher proportion of personal incomes : point is made with respect to government expenditures. Ad-said that the relative decline of the demand for such govern-is schooling, maternal health, etc. will permit a shift of the }lic outlays toward more directly productive investments, rtility may increase female labor force participation rates. 3 in income per capita induced by the fertility decline may ;k effect on labor productivity via better nutrition, health, of the economic effects attributed to fertility change in the two groups.